The federal Centers for Disease Control and Prevention says there are 23 confirmed cases of E. coli and seven probable cases connected to the tainted lettuce. That is up from 19 confirmed by CDC earlier this week.
The rest of those sickened live in Michigan, Ohio and New York. Many of them were middle school, high school and college students who ate in school cafeterias. The CDC said there are 10 confirmed cases in Michigan, eight confirmed cases in Ohio, four confirmed cases in New York and one confirmed case in Tennessee. All of those sickened became ill before late April.
The strain of E. coli involved in the outbreak is rare and difficult to diagnose, so there may be more unreported cases, officials have said.
There have been two recalls of romaine lettuce related to the outbreak, both by distributors who bought lettuce from the same Yuma, Ariz., farm. Ohio-based Freshway Foods announced a 23-state recall of romaine lettuce last week, while Vaughn Foods of Moore, Okla., announced a recall Monday.
Vaughn Foods bought its lettuce from California-based Andrew Smith Co., a supply company which shipped the lettuce after purchasing it from the Arizona farm. The Food and Drug Administration, which is investigating the outbreak, has so far declined to give the name of the farm.